Home › Forums › temp › Part 15 AM legalities, citations, and manufacturers’ advice › TalkingHouse wall adapter grounding
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I have looked at the TalkingHouse wall adapter and it has been specially fabricated (filters added) to reduce conducted emissions down the live and neutral conductors of the house wiring. This transformer adapter is 3-prong and has the ground pin connected to the -ve of the DC output.
When I took the TalkingSign unit in for FCC approval, we failed the conducted emissions at first and had to use a 3-prong switching supply which had commonmode filtering on the line input side which allowed our unit to pass. The problem with both these transmitters is that by their very nature the transmitters are very close to the wall adapter, so its very hard to prevent signals from being conducted down the line.
External tarnsmitters probably don’t have these problems because the transmitter is far away. I believe the Rangemaster just has an ordinary transformer wall adapter.